The invention relates to a method for testing the water resistance of a timepiece, such as a watch and more specifically a wristwatch. It also relates to a method for manufacturing a timepiece which implements said method for testing its water resistance, and to the timepiece such as that obtained by said manufacturing method. Finally, the invention also relates to a system for testing the water resistance of a timepiece which implements said method for testing its water resistance.
The water resistance of a timepiece is an important characterizing feature, and international standards ISO 22810 and ISO 6425 exist for this reason, which standards stipulate various requirements in respect of water resistance, for watches that are simply water resistant and for diver's watches respectively.
The prior art describes various solutions for measuring the water tightness of a timepiece, involving disposing the timepiece inside a closed chamber, inside which it is placed under pressure, and inside which mechanical characteristics are measured, as described in document U.S. Pat. No. 3,991,622, for example.
Document FR2158061 describes a solution for testing the water resistance of a watch, which is supported on a device having a microphone for the purpose of transforming the oscillations of the balance of a watch into an electrical signal and analysing it, in order to measure its rate. This measurement is complicated and not sufficiently reliable.
However, the existing solutions for measuring the water resistance are unsatisfactory. In fact, they include all or some of the following disadvantages:                They require complicated, dedicated equipment based on sensitive components disposed inside pressurization vessels;        They only process the items individually, according to a one-by-one approach;        They are only adapted for a type of item having a given geometry, and they require complex adjustments in order to process another item having another geometry;        They are not adapted for the production on an industrial scale of a large number of items and/or of items having different geometries;        They are only reliable for a part of the water resistance measurements to be carried out, for example being specialized either for the detection of minor leaks or for the detection of major leaks.        